As is well known and understood, personal flotation devices (PFDs) are available in a variety of shapes, colors and materials.
Typically required for recreation boat use, how many, and what type PFDs are required depends on the number of people on board, the size of the boat, and the kind of boating being done.
As is also known, there presently exist two basic types of PFDs--the inherently buoyant vest of a primarily foam composition, and the fully inflatable type activated by a pulling action which punctures a compressed gas cartridge.
While such devices are typically employed by those on boats--fishing, canoeing and kayaking--a very large market exists for those who do not go near the water at all, either because they cannot swim or are afraid to go into the water, but who could benefit through the use of some type of personal flotation device.
My U.S. Pat. No. 5,180,321, issued Jan. 19, 1993 and entitled "Swimmer's Safety Belt" describes a substantially hollow belt, worn about the waist, and able to assume the shape of a life preserver in use, while allowing the wearer to swim to safety after entering the water, using whatever swim strokes may be convenient. As is there set forth, a compressed gas cartridge is employed to fill the belt in allowing the life preserver so formed to ride up to the wearer's arm level.
My U.S. Pat. No. 5,368,512, issued Nov. 29, 1994 and entitled "Inflatable Swimmer's Safety Belt", on the other hand, went further in describing the use of a pair of belts, tethered together, to restrict the life preserver arrangement to rise up to the wearer's arm level, to hold the wearer vertically in the water--thereby obviating the possibility of the life preserver moving over the shoulders and head of the wearer and somehow possibly coming free. With this feature, a life preserver tube was formed of the first belt, tied to the second belt at a length which prevented the tube from slipping over the shoulders and head, even while still allowing the wearer to be able to swim about.
While the safety belts described in these two patents performed quite well from a safety standpoint, the belt described in my further U.S. Pat. No. 5,702,279, issued Dec. 30, 1997 and entitled "Inflatable Swimmer's Safety Belt, Life Preserver/Life Vest" went even further. The safety belt there described could be arranged either as a life preserver, to allow the wearer to continue to be able to swim about, or could be further converted to a life vest, in holding unconscious wearers face-up in the water--or, for use by non-swimmers or children, and for those who could only swim short distances without tiring, while trying to reach shore or to reach a rescue boat. A pair of belts, tethered together, were again used, with the first--substantially hollow and worn about the waist--being able to be filled with the compressed gas in unfolding and expanding outwardly, and with the second underlying the first on the waist. When the first belt was filled with compressed gas, its length increased to form a horizontal tube riding under the arm pits, in holding the wearer vertically as a life preserver, while allowing the wearer to be able to swim about. Couplings were provided on the first belt for maintaining a circular configuration, all the while permitting the tube to be slid over the arms to the shoulders and neck area in continuing to hold the wearer vertically, but this time, as a life vest, keeping the head of the wearer out of the water. As with my U.S. Pat. No. 5,368,512, the tether of this construction prevented the tube from coming loose from the second, or waist, belt and floating away.